Improvement in lifting-jacks



UNITED STATES PATENT OFFICE.

DAVID M. ROSS, OF TEEGARDEN, INDIANA.

IMPROVEMENT IN LlFTlNG-JACKS.

Specification forming part of Letters Patent No. 186.368, dated January 16,1877 application filed November 18, 1876. V I

To all whom it may concern Be it known that I, DAVID M. ROSS, of

tion and operation of the same, reference being had to the annexed drawings, making a part of this specification,and to the letters and figures of reference marked thereon.

Figure 1 of the drawings is a representation of a perspective view of my lifting-jack, and Fig. 2 is a central vertical sectional view of the same.

This invention relates to improvements in lifting-jacks; and it consists in a cylindricalshaped base, which is provided with a lug, which fits into a groovein the movable standard, which standard is provided with several adjusting-holes and enlarged head, which receives the lever.

In the annexed drawings, A represents a hollow base, terminated at its lower end with an extended portion, A. B is a lug, which passes through the side of the base A, and engages with a groove or channel, (J, in the standard D, whereby rotary motion of the latter is prevented. Dis the wrench-standard, which reciprocates in the hollow of the base A. The standard D is provided with several adjusting-holes, a a, through which the pin b passes, suitable perforations being made in the base A for the passage of the pin b. This pin b supports the standard D by passing through the perforations a. The ends of the pin 12 rest in holes in the base A. The upper part of the standard D is enlarged, and slot ted at its upper end, so as to receive .a suitable lever, E, which is secured to the head by pivot 0, upon which the lever works.

By means of the base A, provided with lug B, and vertically grooved or channeled standard D, the adjusting-holes in'the upper standard are always kept in a line with thelholes in the base A, which are adapted to receive the supporting'pin b. i

What I claim as new, and desire to secure by Letters Patent, is

The hollow perforated base A, provided with the lug B, in combination with the standard D, provided with groove 0, perforations a, and the lever E, pivoted to the upper end of said standard, substantially as described, and for the purpose set forth.

In testimony that I claim the above I have hereunto subscribed my name in the presence of two witnesses.

DAVID M. ROSS.

Witnesses:

U. F. TOWNSEND, G. S. POOLE. 

